All that’s standing between Brett Kavanaugh and the Supreme Court is an FBI investigation. A few key senators are waiting to hear if the agency finds some form of corroboration for Christine Blasey Ford’s allegation that Kavanaugh sexually assaulted her in high school.

But lawmakers should be looking into another issue: whether Kavanaugh lied under oath when he testified before the Senate last week, either about the alleged assault or about his pattern of behavior as a young man.

In the heated days that have followed the hearings, a number of people have told the news media that Kavanaugh misrepresented his past. Charles Ludington, a historian at North Carolina State University who went to Yale with Kavanaugh, said in a statement that his friend was not being honest when he “downplay[ed] the degree and frequency of his drinking.” When Kavanaugh “got drunk,” Ludington said, “he was often belligerent and aggressive.” Ludington argued that while “the heavy drinking or even loutish behavior of an 18- or even 21-year-old should [not] condemn a person for the rest of his life,” if Kavanaugh “lied about his actions on national television, and more especially while speaking under oath in front of the United States Senate, I believe those lies should have consequences.”

Lynne Brookes, another Yale classmate, accused Kavanaugh of “blatant lying.” She said that “while at Yale, he was a big partier, often drank to excess,” and that “there had to be a number of nights where he does not remember.”

Senator Lindsey Graham is among Kavanaugh’s most ardent defenders and will likely vote to confirm the judge no matter how many lies he may have told. Back in the 1990s, however, when he was in the House, Graham was at the head of the Republican brigade that came close to bringing down President Bill Clinton for having lied about his affair with a White House intern, Monica Lewinsky. Graham blasted those who dared to pretend that perjury didn’t rise to the level of a “high crime or misdemeanor,” and strongly suggested that lying under oath merited removal for any high-level government official, not just a president.

As the debates got started in the House Judiciary Committee, Graham maintained that Clinton’s behavior was not simply a personal matter. “If this is just about sex with an intern,” he said on November 8, 1998, “and being caught off guard and making false statements but not really having a criminal heart about it, then that’s one thing. But if it’s really about grand-jury perjury, then we’ve got to say, given the context of the situation, is the political death penalty warranted?”

To make their case for impeachment to the House, Graham and other Republicans on the Judiciary Committee held a nine-hour meeting on December 1, 1998, about the consequences of perjury. They hosted two women who were punished for lying under oath about sex. One, Pam Parsons, a former women’s basketball coach at the University of South Carolina, had been imprisoned for four months after a perjury conviction related to a civil libel lawsuit. A second witness, Barbara Battalino, was a psychiatrist for Veterans Affairs who lied in a civil deposition about a sexual relationship with a military veteran who came to her for help. She was still serving under house arrest when she appeared in the House.

Feeling their pain, Graham implored the president to consider the two women’s plight, “real people who’ve suffered real consequences for something that we’re all wrestling with.”

Most House Republicans agreed with Graham’s arguments about perjury. According to then–House Judiciary Committee Chairman Henry Hyde of Illinois: “When the president performs the public act of asking God to witness his promise to tell the truth, the whole truth, and nothing but the truth, that is not trivial. Whether it’s a civil suit or before the grand jury, the significance of the oath cannot and must not be cheapened if our broad boast that we are a government of laws and not of men is to mean anything.”

The House, dominated by Republicans, of course voted to impeach Clinton for making “willfully provided perjurious, false, and misleading testimony to the grand jury.”

During the next phase of the drama, a group from the House—including Graham—took its case to the Senate. Graham insisted that the upper chamber not let Clinton off the hook. In the past, he said, when the Senate had determined that federal judges had committed perjury, it concluded that “you couldn’t in good conscience send him back in a courtroom, ‘cause everybody that came in that courtroom thereafter would have a real serious doubt.”

Even Brett Kavanaugh, who at the time worked for Ken Starr, seemed to believe Graham’s argument. In a vigorous defense of Starr published in The Washington Postin 1999, Kavanaugh and two other attorneys rejected the notion that Clinton had been “trapped” into perjuring himself: “Starr did not cause this; Clinton did. Nor did Starr cause the president later to lie to the grand jury, to parse the meaning of the words ‘is’ and ‘sex’ and on and on. Clinton did all of this with premeditation and on his own. The word that ordinarily describes such behavior is not ‘trapped’ but ‘guilty.’”

Was Kavanaugh trapped? Is he guilty of perjury? If Republicans vote to confirm Kavanaugh to the Supreme Court without at least trying to find out, they should know that “everybody who came in that courtroom thereafter would have a real serious doubt.”

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